by Pete Morris

Created on: March 27, 2008   Last Updated: December 08, 2008

Electronic components, in general, are not expensive; but may be difficult for a hobbyist to obtain. With the huge turnover of equipment in our throwaway, consumer society, it is tempting to recover devices from spent products for use in new projects. There are some things the hobbyist should know before reaping the benefits of this free source of components; safety advice, ways of removing devices without destroying them, and how to identify and verify the newfound bounty.

Safety advice

Wear safety glasses all the time you are dismantling. Pulling soldered joint apart often causes a spray of molten solder; this will sting the skin, but cause severe damage to unprotected eyes. Cutting and scraping will cause flying debris. Some devices, particularly ceramic capacitors, get especially hot when being de-soldered. Watch out for sharp edges in unfamiliar equipment.

Clean removal, wire-ended devices and DIPs

The best way to remove devices is to remove the solder. Single-sided PCBs are easy to do - simply heat the soldered joints and tap the board edge-wise on the bench. Double-sided boards will invariably require a solder sucker (either bulb-type or vacuum-piston); but otherwise you will have to resort to melting each joint separately. If you are lucky, simply heating the solder retaining a device will cause it to slip from the PCB. More usually, however, one lead of a device needs to be heated with the iron and pulled from the board with pliers, and then the other end dealt with. Devices with more than two leads can be removed by heating all the leads together with a large blob of solder.

Clean removal, surface-mount devices

SMDs are easier to deal with than wire-ended ones. You have two options - melt the solder, or scrape the device directly off the surface. Melting the solder is simple, but messy. Just heat both ends of the device with a blob of molten solder on your iron, and tap the board on the bench. The device will fall away, but there is usually some solder splashed over it. Wipe it away with your iron. Scraping the devices off with a small chisel or similar edge tool calls for caution, as with any edge-tool operation. Always cut away from yourself, and wear safety glasses. The devices, even IC packages, suffer remarkably little damage when subjected to this method.

Recording and identification

As you develop a large stock of recovered components, you will find it beneficial to keep records of the type and location of each part. A spreadsheet detailing device

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